Transcriptome profiling reveals key regulatory factors and metabolic pathways associated with curd formation and development in broccoli.

Broccoli, a cruciferous vegetable, has a unique indeterminate inflorescence structure known as curds. It is the main edible organ of broccoli and has a rich nutritional value and health benefits. However, the formation and development mechanism of the curd is still not well understood. In the present study, the shoot apical meristem (SAM) stage and three different development stages of curd (formation stage (FS), expansion stage (ES), and maturation stage (MS)) were identified and subjected to transcriptome sequencing to uncover the potential genes and regulatory networks involved in curd formation and development. The results indicated that the genes associated with the development of SAM such as BolAP1A, BolAP1C, BolCAL, and BolAGL6 play an important role in the abnormal differentiation of the curd apical buds. The genes, BolFRI, BolbHLH89, BolKAN4, BolAGL12, and BolAGL24, displayed significantly differential expression patterns in curd development may function in the regulation of the transition from inflorescence meristem (IM) to floral meristem (FM). Moreover, gene ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) enrichment analysis of the differentially expressed genes (DEGs) indicate that phytohormones, such as auxin (AUX), gibberellins (GA), and abscisic acid (ABA) also play an important role in SAM proliferation and the transition from SAM to IM. In addition, the genes regulating photosynthetic reaction (BolLHCA1, BolLHCB1, BolPsbO, etc.) have a key involvement in the differentiation of secondary IMs during curd expansion. The genes associated with the metabolism of starch and sucrose (e.g., BolSPS4, BolBAM4) were significantly upregulated at the MS should contribute to the maturation of the curd. These findings provide new insights into the potential key regulatory factors and metabolic pathways involved in the formation and development of broccoli curds.

Adsorption of dyes methyl violet and malachite green from aqueous solution on multi-step modified rice husk powder in single and binary systems: Characterization, adsorption behavior and physical interpretations.

A novel modified rice husk (MRH) has been prepared for removing cationic dyes in both single system and binary system. SEM-EDS, FT-IR, XRD and XPS were used to characterize the physical and chemical properties of MRH. It showed that the maximum adsorption capacity of MRH for methyl violet (MV) and malachite green (MG) in single system was 154.49 and 996.97 mg g-1, while in binary system was 530.94 and 408.58 mg g-1, respectively. The experimental results showed that the pseudo-second-order kinetic model was better to describe the kinetic behavior of MV and MG adsorption. By using double layer adsorption model, we found that the nD for MV adsorption were 2.52, 2.65 and 3.34 at 298, 308 and 318 K, respectively, and the nD for MG adsorption were 4.59, 4.85 and 4.30, respectively. These results illustrated that multiple dye molecules were adsorbed on one adsorption site in non-parallel direction, indicating that the adsorption of dyes is multi-molecular mechanism. Furthermore, synergistic and antagonistic adsorption might be existed simultaneously in binary system. In summary, MRH has been shown well adsorption properties and reusability and our finding might provide a new idea for developing low-cost, efficient and reusable adsorbent to remove dyes from wastewater.

BolTLP1, a Thaumatin-like Protein Gene, Confers Tolerance to Salt and Drought Stresses in Broccoli (Brassica oleracea L. var. Italica).

Plant thaumatin-like proteins (TLPs) play pleiotropic roles in defending against biotic and abiotic stresses. However, the functions of TLPs in broccoli, which is one of the major vegetables among the B. oleracea varieties, remain largely unknown. In the present study, bolTLP1 was identified in broccoli, and displayed remarkably inducible expression patterns by abiotic stress. The ectopic overexpression of bolTLP1 conferred increased tolerance to high salt and drought conditions in Arabidopsis. Similarly, bolTLP1-overexpressing broccoli transgenic lines significantly improved tolerance to salt and drought stresses. These results demonstrated that bolTLP1 positively regulates drought and salt tolerance. Transcriptome data displayed that bolTLP1 may function by regulating phytohormone (ABA, ethylene and auxin)-mediated signaling pathways, hydrolase and oxidoreductase activity, sulfur compound synthesis, and the differential expression of histone variants. Further studies confirmed that RESPONSE TO DESICCATION 2 (RD2), RESPONSIVE TO DEHYDRATION 22 (RD22), VASCULAR PLANT ONE-ZINC FINGER 2 (VOZ2), SM-LIKE 1B (LSM1B) and MALATE DEHYDROGENASE (MDH) physically interacted with bolTLP1, which implied that bolTLP1 could directly interact with these proteins to confer abiotic stress tolerance in broccoli. These findings provide new insights into the function and regulation of bolTLP1, and suggest potential applications for bolTLP1 in breeding broccoli and other crops with increased tolerance to salt and drought stresses.

The effect of ultrasonic on reducing anti-browning minimum effective concentration of purslane extract on fresh-cut potato slices during storage.

Enzymatic browning is one of the major difficulties for the preservation and commercial value of fresh-cut products. To research more healthy and inexpensive anti-browning methods, we investigated the effect of ultrasonic coupling purslane extract on the browning resistance of fresh-cut potato during 8d storage at 4 °C. Firstly, the optimal ultrasonic time (10 min) was obtained. Then, the results showed that the combined application with lower purslane extract concentration (0.02%, w/w) could achieve a better anti-browning effect than the optimal concentration of alone purslane extract (0.05%, w/w). The combined application not only significantly inhibited the key enzyme activities of polyphenol oxidase (PPO) and peroxidase (POD), but also effectively reduced the damage to cell membrane, maintained its integrity and permeability. Meanwhile, it also improved antioxidant capacity during storage. Overall, the ultrasonic cavitation combined with purslane extract would be a promising method for fresh-cut industry.

[Trends on the changing prevalence in patients with early syphilis and HIV infection among men who having sex with men in Nanjing, from 2008 to 2013].

OBJECTIVE: To observe the trends on prevalence of early syphilis and HIV infection among men who had sex with men in the last six years from a HIV/AIDS counseling and testing clinic in Nanjing, and to develop relative strategies. METHODS: Men who have sex with men involved in AIDS/HIV and syphilis voluntary counseling and testing services were recruited and investigated from 2008 to 2013 in this clinic. Clients whose syphilis serologic test showed positive were determined the diagnosis by physician within the referral network from sexually transmitted diseases clinics. Demographic information on early syphilis, HIV infection or co-infection with HIV and early syphilis was described while related epidemic trend analysis was performed. RESULTS: The annual numbers of men having sex with men under survey were 1 004 in 2008, 1 218 in 2009, 1 236 in 2010, 748 in 2011, 1 019 in 2012 and 1 420 in 2013. The prevalence rates of early syphilis appeared to be: 2.19% in 2008, 2.71% in 2009, 2.43% in 2010, 1.74% in 2011, 3.04% in 2012 and 2.32% in 2013, with the trend as: P > 0.05. The prevalence rates of HIV infection were 1.29% in 2008, 2.63% in 2009, 5.42% in 2010, 8.82% in 2011, 11.97% in 2012 and 10.42% in 2013, with trend as: P < 0.01. The prevalence rates of early syphilis with HIV infection increased from 0.20% in 2008 to 1.06% in 2013 (trend: P < 0.01). The proportion of HIV co-infection among men having sex with men with early syphilis infection, increased from 9.09% in 2008 to 45.45% in 2013, with trend: P < 0.01. CONCLUSION: Early syphilis infection among men who having sex with men showed a stable trend but the number of HIV and co-infections with early syphilis and HIV increased rapidly in the last six years in Nanjing. Continued intervention strategies should target on men who have sex with men to slow down the epidemic of syphilis and HIV infection.